Since yesterday affernoonn, whenever I eat something, the right side of the front of my neck beneath the chin gets tight and swells up.?

Salivary gland stone. A stone blocking the salivary gland duct, most commonly the submandibular duct, is called sialolithiasis. Warm compresses, drinking plenty of fluids, and sucking on sour candy can help dislodge the stone. If it continues, antibiotics and surgery may need to be necessary.